Wind turbines include large and heavy parts such as a nacelle, a generator, a rotor, a gearbox, tower sections and the like. Such large and heavy parts should be handled, e.g. lifted, etc., usually in manufacturing, installation, transport, repair and replacement operations, through the use of lifting equipment such as lifting cranes or the like. The weight and the size of said large and heavy parts to be handled result in that said manufacturing, installation, transport, repair and replacement operations are difficult to be carried out. In addition, cranes used for lifting such parts are bulky and expensive, especially in offshore environment.
A number of solutions for lifting wind turbine parts have been proposed in the art. Lifting tools, such as lugs, hooks or the like are attached to the wind turbine part to be lifted which may be, for example, a structural component, by means of bolted connections.
WO2005071261 discloses the use of a tool for handling a wind turbine blade. The tool comprises two bracket-like components between which the blade is attached. Tool attachment is carried out by bolts extending through blade mounting holes. Each bracket-like component comprises a plate having the same profile as the blade and provided with flanges having a fastening hole.
U.S. Pat. No. 8,562,302 discloses a wind turbine blade having a structure for handling the blade. Such handling structure comprises attachment bores having threaded female channels for receiving a handling mechanism. Said attachment bores are formed in structural members engaged with internal spar caps extending within the blade.
Although current solutions are technically efficient, they use bolted, i.e. threaded, connections to attach the handling components to the wind turbine part to be lifted. This results in that disassembling operations take a long time and involve undesirable additional costs together with unsafe conditions for workers who have to perform operations in risky sites of the wind turbine under unsafe conditions at large heights, such as outside the nacelle, while the lifting equipment might be still in operation. In addition, removal of bolts must be carried out through the use of hydraulic tools which are heavy and require electric and/or hydraulic power to be operated and which also have to be transported up to such critical positions.